Co-precipitates of lumefantrine-Eudragit E PO for dissolution improvement

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Enzymatic activity in the presence of surfactants commonly used in dissolution media,Part 1: Pepsin

The United States Pharmacopeia (USP) General Chapters Dissolution 〈711〉 and Disintegration and Dissolution of Dietary Supplements 〈2040〉 allows the use of enzymes in dissolution media when gelatin capsules do not conform to dissolution specifications due to cross linking. Possible interactions between enzymes and surfactants when used together in dissolution media could result in loss of the enzymatic activity. Pepsin is an enzyme commonly used in dissolution media, and in this work, the activity of pepsin was determined in the presence of different surfactants as usually found in case of dissolution tests of certain gelatin capsule formulations.Pepsin enzymatic activity was determined according to the Ninth Edition of the Food Chemicals Codex (FCC) 9 method, in dissolution conditions: simulated gastric fluid, 37 °C and 50 rpm. Sodium dodecyl sulfate (SDS), cetyltrimethyl ammonium bromide (CTAB), polysorbate 80 (Tween 80) and octoxynol 9 (Triton X100) in concentrations above and below their critical micellar concentrations were selected. Results showed a significant reduction in the activity of pepsin at all the concentrations of SDS assayed. On the contrary, CTAB, Tween 80, and Triton X100 did not alter the enzymatic activity at of pepsin any of the concentration assayed.This data demonstrates a rational selection of the surfactant to be used when pepsin is required in dissolution test.     

An eco-friendly HPLC-UV method for the determination of risedronate in its bulk and tablet dosage form with application to content uniformity,dissolution and stability testing

Risedronate is a nitrogen-containing bisphosphonate for the treatment and prevention of postmenopausal osteoporosis. The current work aims to develop a novel green HPLC-UV method for the rapid analysis of risedronate sodium in bulk and tablet formulation. The analyzed samples were separated on Waters Atlantis dC18 (150 mm × 3.9 mm; 5 μm) column using a green mobile phase consisting of potassium phosphate buffer pH 2.9 and potassium edetate buffer pH 9.5 in a ratio of 1:2, the final pH was adjusted to 6.8 with phosphoric acid, the mobile phase was pumped at a rate of 1.0 mL/min, with column temperature set at 30 °C, eluted samples were detected at 263 nm and the chromatographic run time was 3.0 min. The method was found to be linear over the concentration range of 14–140 μg/mL with a correlation coefficient (r²) of 0.9994. Accuracy and precision were evaluated from three QC samples (LQC, MQC and HQC) together with the five calibrators where the percentage accuracy was found to be 101.84%. Processed quality control samples of risedronate sodium were tested for stability at different conditions, short term, long term and freeze- thaw stability. The current method was further extended to study the content uniformity of Actonel® tablets following United States Pharmacopoeia (USP) guidelines. The proposed method was fully validated as per ICH guidelines.     

In vitro dissolution and oral bioavailability study of fenofibrate nanomatrix system prepared by hot-melt extrusion

Solvent evaporation method for preparation of nanomatrix has the disadvantages, such as residual organic solvent, environmental pollution, explosion-proofing and so on. To overcome these shortcomings, a series of fenofibrate nanomatrix drug delivery system (NDDS) consisting of nano-porous silica Sylysia^®350 (S350) and pH sensitive material Eudragit^® L100-55 (EL100-55) were prepared using hot-melt extrusion (HME), and their in vitro dissolution and in vivo bioavailability were compared. Finally, the formulation with the highest in vivo bioavailability was selected as the optimized formulation for DSC and PXRD characterization. The results showed that the optimized NDDS showed a higher bioavailability than the reference formulation, although there was crystalline form drug remaining in NDDS. The relative bioavailability of the optimized formulation was 157.1% compared with the commercial product Lipanthyl^®. In addition, the relative bioavailability of the optimized formulation was 124.8% in comparison with the formulation prepared by solvent evaporation method, showing that the NDDS prepared by the HME method was effective in improving the bioavailability of fenofibrate. In conclusion, HME was a promising method to prepare NDDS.     

The natural bile acid surfactant sodium taurocholate (NaTC) as a coformer in coamorphous systems: Enhanced physical stability and dissolution behavior of coamorphous drug-NaTc systems

The amorphization of 18 different drugs on milling with one mole equivalent sodium taurocholate (NaTC) was investigated. In all cases the X-ray powder pattern showed an amorphous halo after milling at room temperature or after cryomilling and 14 of the 18 coamorphous drug-NaTC systems were physically stable for between one to eleven months under ambient storage conditions. In three cases, namely carbamazepine-NaTC, indomethacin-NaTC and mefenamic acid-NaTC, significant dissolution advantages over the crystalline drugs were observed, both for the freshly prepared samples and after storage for seven months. To understand the increased physical stability, infrared-, near-infrared and Raman spectroscopic studies were carried out. The effectiveness of NaTC as a coformer in a diverse range of coamorphous systems is attributed to its awkward molecular shape that hampers recrystallization and phase separation and its propensity to form a range of similar, yet different drug-coformer hydrogen bonding arrangements.     

国产地氯雷他定片溶出度方法的建立

目的： 建立有效区分地氯雷他定片质量并具有国际通用性的溶出度HPLC测定方法。 方法：采用桨法,以0.1 mol.L-1盐酸溶液为溶出介质,转速50 r.min-1,采用高效液相色谱法测定溶出度,以辛烷基硅烷键合硅胶为填充剂,流动相为甲醇-0.5%三氟醋酸溶液(用三乙胺调pH值至6.3)(55:45),流速：1.0ml.min-1,柱温：30℃,检测波长247 nm。结果：地氯雷他定在1.02~204.20μg.mL-1的浓度范围内,线性关系良好(r=1),平均回收率为100.5%,RSD为0.3%(n=9),国内片剂在30min时的溶出度均在95%以上。结论：本方法准确、简单方便且高效,测定结果均一性良好,可有效地用于地氯雷他定片溶出度的测定。     

Developing a quality by design approach to model tablet dissolution testing: an industrial case study

Abstract

This study applied the concept of Quality by Design (QbD) to tablet dissolution. Its goal was to propose a quality control strategy to model dissolution testing of solid oral dose products according to International Conference on Harmonization guidelines. The methodology involved the following three steps: (1) a risk analysis to identify the material- and process-related parameters impacting the critical quality attributes of dissolution testing, (2) an experimental design to evaluate the influence of design factors (attributes and parameters selected by risk analysis) on dissolution testing, and (3) an investigation of the relationship between design factors and dissolution profiles. Results show that (a) in the case studied, the two parameters impacting dissolution kinetics are active pharmaceutical ingredient particle size distributions and tablet hardness and (b) these two parameters could be monitored with PAT tools to predict dissolution profiles. Moreover, based on the results obtained, modeling dissolution is possible. The practicality and effectiveness of the QbD approach were demonstrated through this industrial case study. Implementing such an approach systematically in industrial pharmaceutical production would reduce the need for tablet dissolution testing.     

磷酸西格列汀片处方工艺研究

目的 筛选磷酸西格列汀片的最佳处方工艺。方法 设计不同处方工艺,通过检测溶出曲线及粉体学数据,确定最佳处方工艺。结果 自制片的4个处方中,粉体学数据及压片流畅性均较好,其中湿法制粒工艺两个处方溶出比参比制剂慢,粉末直压工艺中当交联羧甲基纤维素钠为16 mg时溶出曲线与参比制剂拟合较好。结论 通过对磷酸西格列汀片的处方工艺研究,最终确定了磷酸西格列汀片的工艺和崩解剂用量。     

用多条溶出曲线评价盐酸氟桂利嗪胶囊的质量

目的 研究国产盐酸氟桂利嗪胶囊与参比制剂在4种溶出介质中的溶出曲线,以评价该制剂的质量。方法 考察盐酸氟桂利嗪原料在pH 1.2盐酸溶液、pH 4.0醋酸盐缓冲液、pH 6.8磷酸盐缓冲液和水中的溶解度与稳定性,并采用篮法,转速为100 rpm,优化盐酸氟桂利嗪胶囊溶出度测定的溶出介质,测定溶出曲线,并用f₂因子法进行比较分析。结果 以A企业某进口本地化的上市产品为参比制剂,B、E企业只有在pH 1.2盐酸溶液中与参比制剂溶出过程相似,C企业在pH 1.2盐酸溶液和水中与参比制剂溶出过程相似,D企业在pH 1.2盐酸溶液和pH 4.0醋酸盐缓冲液中与参比制剂溶出过程相似。选择pH 4.0醋酸盐缓冲液作为测定盐酸氟桂利嗪胶囊溶出度的溶出介质。结论 国内仿制药与参比制剂在内在质量上存在差距,仍需在处方工艺和生产过程控制方面有所改进。     

甲苯磺酸索拉非尼片的制备以及体外溶出行为考察

目的：制备甲苯磺酸索拉非尼片并考察其体外溶出行为。方法：以交联羧甲基纤维素钠为崩解剂,微晶纤维素为填充剂,十二烷基硫酸钠为增溶剂,制备本片。以f2值为考察指标,采用正交设计法筛选最优处方。结果：在不同溶出介质中,自制制剂的溶出曲线和进口制剂的体外溶出特征相似。结论：按优化的处方工艺制备的本片符合规定,可操作性强;溶出动力学特征符合一级方程。